Windows users

Using the freeware CPU-Z you can determine whether your CPU is 64-bit compatible.
CPUs with AMD's instruction set "AMD64" or Intel's solution "EM64T" should be compatible with the x86_64 releases and binary packages.

How can I install Arch64?

How complete is the port?

Will I have all the packages from my 32-bit Arch I am used to?

The repositories are ported and pretty much everything should work as expected.

Rarely, an old package in the AUR will only have 'i686' listed, but typically they work for 64-bit too. Just try adding 'x86_64'.

Why 64-bit?

It is faster under most circumstances and as an added bonus also inherently more secure due to the nature of Address space layout randomization (ASLR) in combination with Position-independent code (PIC) and the NX Bit which is not available in the stock i686 kernel due to disabled PAE. If your computer is running 4 GB or more of usable RAM, 64-bit should be strongly considered as any additional RAM cannot be allocated by a 32-bit OS.

Programmers also increasingly tend to care less about 32-bit ("legacy") as "new" x86 CPUs typically support the 64-bit extensions.

There are many more reasons we could list here to tell you to avoid 32-bit, but between the kernel, userspace and individual programs it is simply not viable to list every last thing that 64-bit does much better these days.

For further details watch our differences reports. There you will find a list comparing 32-/64-bit package versions.

How can I file bugs?

Simply use Arch's Flyspray but select x86_64 in the Architecture field if you think it is a port-related problem!

What repositories should I set up for pacman to use?

All repositories are supported for the port.

How can I patch existing PKGBUILDs for use with Arch64?

Add the following variable to all ported packages:

arch=('i686' 'x86_64')

Add small patches directly to the sources and md5sums area but use for complete different sources:

What will I miss in Arch64?

Nothing, really. Almost all applications support 64-bit by now or are in the transition to become 64-bit compatible.

The biggest problem are packages that are either closed source or contain x86-specific assembly that is cumbersome to port to 64-bit (typical for emulators).

These applications were previously problematic but are now available in the AUR and work fine:

Acrobat Reader is not available in 64-bit, but you can run the 32-bit version in compatibility mode. There are also many other open source alternatives that can be used to read PDF files.

Everything else should work perfectly fine. If you miss any Arch32 package in our port and you know that it will compile on x86_64 (perhaps you have found it as native packages in another 64-bit distribution), just contact the developers or request a new package in the forums.

Can I run 32-bit apps inside Arch64?

Yes!

You can install lib32-* libraries from the [multilib] repository. To use this repository, you should add the following lines to your /etc/pacman.conf:

Some 32-bit apps (like OpenOffice) may require additional bindings. The following lines can be placed in /etc/rc.local to ensure you get all you need for the 32-bit apps (assuming /mnt/arch32 is mounted in /etc/fstab):

Chroot

This article or section is out of date.

Reason:please use the first argument of the template to provide a brief explanation. (Discuss in Talk:64-bit FAQ#)

To use an i686 chroot (installation with i686 ISO "quickinstall" is recommended for the quick way to install it inside Arch64 or see Arch64 Install bundled 32bit system), install "linux32" wrapper pkg from current to make the chroot behave like a real i686 system. Then use this script to login into the chroot environment as root:

to share sources from host to chroot system for pkg building used in /etc/makepkg.conf.

Can I upgrade/switch my system from i686 to x86_64 without reinstalling?

Yes. A forum thread has been created here which outlines steps taken to successfully migrate an install from 32 to 64 bit without losing any configs/settings/data. Note: A large external hard drive was used for the transfer.

However, you can also start the system with the Arch64 installation CD, mount the disk, backup anything you may want to keep that is not a 32-bit binary (e.g: /home & /etc), and install.